With Ubuntu 12.10 and a nvidia card, sometimes my monitor won't turn back on when the machine returns from hibernate mode. Actually it may not be the monitor but the system won't recover so I have to reboot. I tested the memory and that is working. The hard-drive seems to be fine. I usually run all the updates, hopefully an update will fix the problem.

Has anyone experienced this? It is intermittent, maybe two times a week after running it continuously.

This script should work or your money back guaranteed (Joking this is
open source project so use at own risk :P ), as it forces the graphic
card to reboot iself using a good old kick from chvt1 and chvt7
commands which simulate what I used to do manually using Ctrl+Alt+F1 and Ctrl+Alt+F7 to refresh the GUI.